I own a Lulzbot Taz 5, I have had it for approximately 2 months.
- I’ve had maybe a hundred+ good prints, a comparable number of failures, and an unfortunate amount of debilitating jams.
- I regularly level my print bed.
- I clean my extruder thoroughly, before and after jams.
- I keep my filament in a dry environment, practically swimming in little packs of silica gel.
- I regularly swap out the 3mm hot end for a hexagon 1.75mm hot end (purchased 3rd party) when the hot end currently in use jams up and I need to soak it in acetone to clean it out.
- Up until today, I have exclusively printed with ABS. (esun 3mm, hatchbox 1.75mm)
- I love my machine.
The above now established, I will move on to the “meat and potatoes” of my post.
The first time I powered on my machine and heated the hot end, a tiny puff of smoke come out of the heat sink fan. It seemed to be operating properly, and being engrossed in the setup process and general excitement of getting started, I mindlessly thought nothing of it. I proceeded to use my machine with varying success for about a month.
One day, while soaking my hot end in acetone to clear out a jam, I began searching the forum for posts regarding whether or not it was possible to utilize 1.75mm filament with the stock hot end. I stumbled upon a few threads that suggested it was possible. Having received a 3d printing pen as a gift a couple months prior to ordering my machine, I had a few rolls of 1.75mm filament handy and decided to give it a try. The filament buckled just past the hobbed bolt every time, and after a weekend of tinkering with it, I ended up ordering a 1.75mm hexagon hot end kit from a 3rd party website. I have been using it with the same varying rate of success as my 3mm hexagon. Only swapping out the hot end, still using the stock heater and thermistor.
Today, (after a jam in my 1.75mm hot end) I reattached my 3mm hotend and decided to try my luck printing with a roll of esun 3mm PLA that I had received about a week prior. This being my first attempt at printing with PLA, I was discouraged with the amount of trouble I’ve had. The extruder leaks so much that I have been unable to print even a 20mm cube without the extruder jamming.
Every time I either:
- insert filament into the pre-heated hot end, or
- slowly heat the hot end with filament inserted and then manually (from pronterface, or by hand) extrude some filament to get the end primed:
A vast quantity of filament rapidly leaks out of the nozzle. From what I can tell, this results in two things:
- a cavity of air forms between the opening at the hobbed bolt and the nozzle, and / or
- the nozzle ends up with either a giant glob of PLA stuck to it, entirely coated in PLA, or jammed up altogether.
I tried the following to remedy the leaking:
- altering Slic3r retraction settings, trying a number of configurations
–a) did not expect this to solve the problem, as the leaking occurred constantly. Not just when printing - replaced the stock thermistor with the one that came with my 1.75mm kit
–a) thought maybe the stock thermistor was malfunctioning and the hot end was going past the ~205c I was setting it at
Neither of these things solved the problem.
I got my hands on an infrared thermometer and everything became clear to me. With my hot end set at 205c, the heat sink just below the mounting plate was reaching ~160-170c. Heat is creeping up my hot end assembly.
I am now reminded of the tiny puff of smoke that came from my heat sink fan at the time of my initial set up and I am inclined to believe the fan has not been operating consistently since.
I am hoping that this is the source of the issues I have been experiencing, as replacing a fan sounds a lot easier than everything else I’ve been doing.
Hoping I can get my hands on a replacement heat-sink fan.
